[Primary Clear Cell Carcinoma of the Gall Bladder-A Case Report].

A 76-year-old man presented to our hospital with a chief complaint of pain in the right quadriceps. Various imaging tests revealed suspected peritoneal dissemination in gallbladder carcinoma. In October 2021, the patient underwent laparoscopy and a disseminated nodule was sampled. The patient was diagnosed with Stage Ⅳ gallbladder cancer. Histopathological examination revealed an adenocarcinoma classified as clear cell carcinoma. No neoplastic lesions were found in other organs, consistent with a primary gallbladder origin. The patient had received chemotherapy(GEM+CDDP)for approximately 1 year. Although computed tomography(CT)showed marked shrinkage of the lesion, positron emission tomography/CT revealed distant metastasis to the xiphoid process. The treatment regimen was switched to GEM+S-1. Despite this adjustment, the disease worsened, and the patient succumbed to the illness 1 year and 8 months after surgery. We report this case along with a literature review owing to the rarity of clear cell carcinoma of the gallbladder.